Apparatus for skywriting



WITNESS:

1,632,153 1927' E. THORESEN APPARATUS FOR SKYWRITING v Filed May 28, 1926 2 Sheets-Sheet 1 I Eehernama g h: whim ATTORNEY I 14 l June 927 E. THORESEN APPARATUS FOR SKYWRITING 2 Sheets-Sheet 2 Filed May 28. 1926 q I EE -F E1 lull ll ll E "E ME .ATTQRNEY wwyuass:

' Patented June 14, 1927.

UNITED STATES PATENT orl-ica.

EI'NAB TEOBEBEN, OI PITTSBURGH, PENNSYLVANIA,

APPARATUS FOR SKYWRITING.

Application filed Kay 28, 1928, Serial No. 112,884, and in Norway J'une 8,19.

My present invention relatesto a'skywriting device for automatically writing words, numerals and pictures in the sky with thev use of smoke.

My object is to provide a device carried by an aeroplane or other like flying craft which will semi-automatically project a plurality of smoke bombs, so timed and controlled that they will explode at different altitudes and in different positions in the sky, so-that when exploded these bombs will clearly describe a letter, figure or design in the sky which will be clearly seen from the ground.

A further object is to provide a flying craft with a belt or conveyor that travels over a suitable table or like support and which has one end wound around a roller attached to and designed to be wound on a second roller by motor driven means, said belt having spaced series of openings therethrough to form letters, designs or figures, and each of said openings adapted to receive therein a smoke bomb of a particular and peculiar construction whereby such bombs will-be moved by the belt, in'proper timed relation with respect to, each other and caused to" drop through an opening in the bottom of the craft, and which bombs are timed and controlled to explode at different altitudes in the sky to clearly describe letters, figures or designs which are clearly seen from the ground either in the day or at night time, and further wherein the bombs may be difierently colored if desired. Q

To the attainment of the foregoing broadly stated objects and others which will present themselves as the nature of the mvention is better understood, the improvement resides in certain novel features of construction, combination and operative association of parts, 'one satisfactory embodiment of which is illustrated by the ac companying drawings.

Inthe drawings: Figure 1 is a diagrammatic view to illustrate the manner in which the smoke bombs are dropped from the aero lane and the different altitudes at which nibs explode to produce a letter, figure, design or signal.

Figure 2 is a top plan view of the belt or conve there or.

Figure 3 is a sectional view approximately on the line 33 of Figure 2.

Figure 4 is a sectional view on the line of Figure 2.

Figure 5 is a sectional view on the line 5-5 of Figure 2.

Figure 6 is a side elevation of one of the bombs.

Figure 7 is a bottom plan view thereof.-

Figure 8. is a sectional view approximately on the line 8-8 of Figure 6.

The numeral 1 designates an aeroplane or like flying craft in which the operating mechanism of the improvement is mounted." The lmprovement contemplates the em loyment of a conveyor in the nature of a' and which is preferably of canvas and which is preferably indicated by the numeral 2.. The conveyor 2 has one end fastened to and wound around a cylinder 3, and its other end secured to and designed to be wound. on a cylinder 4., Both of the cylinders have their trunnions journaled in suitable upor and the operating mechanism standing bearings, and the cylinder 4 has on one of its trunnions a toothed wheel 5 which is in mesh with a pinion 6 onthe shaft of a motor 7. The motor may be of a small electric type which may employ a storage battery but the same may bespring wound if desired. .On the floor of aeroplane 1, I secure the base 8 of a table 9. As disclosed by the drawings, the elements 8 and 9 are preferably constructed of blocks and the t le top 9 is provided with equidistantly spaced" longitudinally arranged grooves 10 and these grooves arev designed to be disposed opposite substantially rectangular openings 11 in the conveyor 2.

V The series of openings 1Lare so arranged as to form letters, characters or designs, and the series of openin disclosed on the con veyor in Figure 2 o the drawings show the letters F and T. .The top f the table rojects a suitable distance beyond the ase thereof at the end of the table next to the cylinder 4, and fixed on this end of ,thebase,

in a line centrally with respect to each of the grooves 10,-there is the inner arm of an upstanding hook 12. I The lower wall of the table 'top, at the ortion thereof which pro jects beyond the ase, is cut-away in a line with the grooves so that the inwardly directed beaks 13 of the hooks 12 are received in these cut-away portions.

Designed to be passed through each of the openings 11 and to be received in the res ective grooves 10 are the smoke bombs. T ese bombs, of course, are so arran ed before the writing is started oi while t e writing is underway. Each smoke bomb includes a substantially rectangular casing 14 of noninflammable thin pasteboard provided with a closed top and a base 15 which is elevated above the ends of the sides of the bomb. Above the base 15'there is a second base 16, which provides the bottom proper and affords a compartment between the said bottom and the base 15. The bomb, of course, isfilled with a smoke producing powder 17, and secured centrally in each bomb between the top and the bottom 16 thereof, there is a non-inflammable tube 18 in which one end of a fuse 19 is arranged. A detonator or other firing device" 20 is connected to the outer end of the tube, and to this element 20 there is secured a cord or like flexible element 21 which is coiled upon itself and arranged in the. com artment 22 between the walls 15 and 16 0 the bomb. The end of the element 21 passes through a central opening in the base 15 and has secured thereto a ring member 23 which is received in a space 24 below the base 15. The bombs are arranged in the staggeredly related openings 11 of the conveyor 2 so that the edges of the sides of what may be termed the open bottom of the bombs will rest on the lower walls of the guide grooves 10. The bottom of the flying craft, directly between the hooks 12 and the cylinder 4 has an opening 25 therethrough.

We will assume that the flying craft 1 in Figure .1, is-just starting to write the letter F. The motor 7 is in operation so that the conveyor band is moving off of the cylinder 3 and onto the cylinder 4. The conveyor has been moved a distance to permit of the dropping of the first bomb, A, (Figure 2) through the opening 25 in the flying craft. The moment before the bomb A drops through the opening the ring 23 is caught on the hook 12. lVhile the bomb drops through the opening the string 21 will be ullcd out of the bomb, and when the bomb as dropped 10 feet, (the length of the string 21) the firing device 20 is set in motion to ignite the fuse 19. The shock which occurs. while the string pulls the firing device will not in any from falling freely.

While the flying craft is flying at a steady speed in the same direction the opening 25 arrives to the lineb (Figure 1) the bomb drops through the opening and explodes at degree hinder the bomb a point 2'.

To complete the letter F the bombs are dropped from the aeroplane as follows:

W en the opening 25 is on the line 0, (Fig. 1) bomb 0 drops to point 3'.

When the opening 25 is on the line (I, (Fig. 1) bomb D drops to point 4'.

When the opening 25 is on the line e, (Fig. 1) bomb E drops to point 5.

. When the opening 25 is on the line f, (Fig. 1) bomb F drops to point 6'.

When the opening 25 is on the line g, (Fig. 1) bomb G drops to point 7 When the opening 25 is on the line h, (Fig. 1) bomb H drops to point 8 When the opening 25 is on the line i, (Fig. 1) bomb I drops to point 9'.

When the opening 25 is on the line k, (Fig. 1) bomb K drops to point 10.

In a similar manner other letters may be written.

The height of the letter shown in Figure l is 2000, ft., and it will be understood that bomb A drops 2400 ft., before exploding, bomb B drops 1900 ft., before exploding, bombs C,.F, and H drop 1400 ft., before exploding, bomb D drops 900 ft., before exploding and bombs E, G, I and K drop 400 ft., before exploding.

To secure any other height of the smoke letters it is only necessary to adjust the bombs to explode at different altitudes than shown and it is to be understood that the cylinders 3 and 4 may be spaced away from each other any desired distance so that openings 11 representing more than two letters or figures may be arranged over the table, in which instance the table is, of course, also lengthened.

It will be seen that an essential idea of this device is the very simplicity of making the holes in the belt and to let the belt actas a conveyor for the bombs.

When the skywriting is finished the rings 23 carrying the strings 21 may be removed from the hooks before the aeroplane makes a landing.

With my improvement the ignition of the fuse and the explosion of the bombs occur underneath the flying craft, thus removing any danger of the bombs being exploded in the craft. All the bombs are of the same construction with the exception of the difference in the length of the fuse to provide ex losions of the bombs at different altitu es.

To write small letters it is possible to use bombs without any fuse. In this case the string is made that long so the bombs will explode directly from the ignition device and the aeroplane will travel at a very slow speed. The device may be also used to project other signaling devices, for instance, small parachutes, etc., which parachutes are made to open at different altitudes. Instead of placing the strings in the bombs, it is also possible to have five strings of different lengths fastened to the aeroplane and let the bombs slide along said strings and when the bombs reach the end of the string the firing device is pulled out and the bomb exploded, Thetube 18 in the bomb is provided with one or more holes in the upper part thereof, through which holes the fuseignites the smoke powder.

Night skywriting is produced through the use of pyrotechnics, parachute flares or the like, which are projected in a manner as above described.

Having described the invention, I claim 1. In a skywriting device, the combination of smoke bombs arranged in positions to represent letters, figures or the like, a longitudinally movable belt on which the bombs rest, means for imparting a motion to the belt to cause the bombs to drop singly therefrom, and means for causing the explosion of the bombs at difi'erent altitudes in the air.

2. In a skywriting device, a conveyor belt having openings therein arranged to represent letters, figures or the like and each of said openings adapted for the reception of 'asmoke bomb, guide means for the bombs below the b.elt,means for imparting a longitudinal movement to the belt to cause the bombs to travel over the guide means and to singly drop from the belt, and means for causing the explosion of the bombs at different altitudes in the air.

' 3. In a skywriting device, the combination with an air craft, having an opening in the bottom thereof, a conveyor belt arranged over the opening and projecting therebeyond, said belt having spaced series of openings therethrough to represent different letters, figures or the like, a smoke bomb adapted to be received through each opening, a table below the belt disposed to one side of the opening, and providing a guide for the bombs, and means for imparting a longitudinal movement to the belt, timed with respect to the speed of the air craft whereby the bombs will be singly moved off of the table and dropped through the opening in the air craft, in combination with means for causing the explosion of the bombs at different altitudes in the air.

4. In a skywriting device, the combination with an air craft having an opening in the bottom thereof, a conveyor belt in the craft, a cylinder on which the conveyor belt is wound, a second cylinder on which the conveyor'belt is to be wound, means for revolving the last mentioned cylinder in timed relation to the flight of the aeroplane, said smoke bombs designed to be received through each of the openings in the belt and to rest on the lower walls provided by the grooves in the table and whereby such bombs will be singly dropped through the belt and through the opening in the craft, and means for causing the explosion of the bombs at different altitudes in, the air.

5. In a skywriting device, the combination with an air craft having an opening in the bottom thereof, a conveyor belt in the craft having one portion thereof extending over the opening, said belt having spaced openings therethrough, arranged in series to represent letters, figures or the like, a table below the belt and disposed to one side of the opening in the craft, said table having its top grooved longitudinally in a line with the openings in the belt and having books on the ends thereof in a line with said grooves and which hooks are disposed opposite the opening in the craft, a smoke bomb adapted to be received through each opening in the belt and to rest on the lower walls provided by the grooves in the table, each of said bombs having an explosive smoke powder chamber therein, a fuse, a firing device for the fuse, a cord housed in the-bomb and connected with the firing device, a ring secured to the cord, each of said rings being in the path of engagement with one of the mentioned hooks, whereby the bombs will be suspended and exploded at different determined altitudes in the sky when the conveyor belt is moved longitudinally to bring the said bombs singly over the opening in the air craft, and the fuses of the several bombs being of different lengths for so timing the explosion of the bombs. i

In testimony whereof I afiix my signature.

EINAR THORES EN. 

